Ground rods or electrodes are widely used in many applications and usually comprise interconnected sections of copper jacketed, coated or plated steel rod which are coupled together and driven into the ground. Conventionally, such rods come in sections and are literally pounded into the earth or ground with sections being added as the rod moves into the earth. Ground rods are inserted in much the same manner as pilings and are thus subjected to considerable abuse in the insertion process. In a ground rod assembly, the coupling is normally the point of highest electrical resistance.
In conventional threaded couplings, bronze or brass coupling sleeves are employed which are internally threaded. Such sleeves are normally made from either bar stock or heavy-walled tubular stock and are quite expensive. More importantly, the materials employed in such couplings or fittings do not provide good conductivity from one rod section to another.
It is accordingly desirable to provide a ground rod assembly and coupling therefor which incorporates the high conductivity or low resistance of copper and which also has strength and corrosion resistance.
It is also desirable that such a coupling be capable of manufacture in an inexpensive and convenient manner.